How Bad Is Your Sandwich for the Environment?

It’s the staple lunchtime option for Brits up and down the country – whether you favour chicken salad, all-day breakfast or the traditional ploughman’s, we all like to tuck into a sandwich for our midday sustenance.

However, a new report from the University of Manchester has suggested that the humble sarnie might have a greater impact on our planet than previously thought. By assessing 40 different varieties of the 11.5 billion sandwiches eaten in the UK every year, researchers were able to ascertain an approximate carbon footprint for this most popular of British foodstuffs.

Over 8 million cars

The scientists took into account a range of factors for the study, including the environmental costs of agricultural production and the subsequent preparation and processing of the ingredients, as well as the packaging of the final product, its transportation to various outlets around the country and the energy expended in keeping it chilled in a refrigeration unit.

The results showed that the cumulative emissions generated by this single industry amounted to approximately 9.5 tonnes of carbon dioxide equivalent (CO2 eq) every single year. For comparison, that’s roughly the same the carbon footprint of 8.6 million cars on an annual basis. When framed like that, the environmental effect of the lowly sandwich is staggering.

Contributing factors

Carbon emissions from agriculture and dairy farming were by far the biggest contributing factor – and that’s without even accounting for methane emissions generated by the same industry. Production and processing amounted to between one- and two-thirds of the total sum, depending on the individual ingredients.

Packaging, which supermarkets in particular have come under fire for in recent times, contributed a relatively small amount to the total at only 8.5%. Transportation emissions were even less at just 4%.

However, refrigeration of the product was a major factor, with around 25% of total emissions attributable to fridges and the suchlike. Perhaps such an outcome should be expected in the wake of revelations that one million refrigeration units are equivalent to 56 million diesel cars in terms of their environmental impact.  

The sandwich leaderboard

As is to be expected, home-made sandwiches are far more eco-friendly than pre-packaged, store-bought options, since they involve less processing, packaging and refrigeration. The old favourite of homemade cheese and ham was the least damaging to the environment, emitting between 399 and 843g CO2 eq depending on the method of preparation.

Any sandwich containing bacon, cheese, ham, prawns, sausages or tomato were found to be particularly damaging to our atmosphere, especially if store-bought. The worst offender of them all was the sturdy all-day breakfast combination of bacon, egg and sausage, which released a whopping 1,441 CO2 eq – over four times that of the most eco-friendly option.